It is 4am on the emergency ward of Evangelismos general hospital - the biggest in Greece - and the stream of patients is relentless. Dr Michalis Samarkos has not stopped working since he started his shift some 14 hours earlier, and he has been besieged by patients unable to afford the tests or the drugs they need.

Many, like the unemployed diabetic man he has just examined, have gone without treatment for several days. "When you see a diabetic unable to afford his insulin you know he is going to die," says Samarkos. "There is no infrastructure to help these people. On every front the system has failed the people it was meant to serve."

Greeks are paying for their economic disaster with their health, according to a new study.

In a letter to the Lancet medical journal, a team lead by Dr Alexander Kentikelenis and Dr David Stuckler from Cambridge University and Professor Martin McKee from the London School of Hygiene and Tropical Medicine warns of a potential "Greek tragedy". They point to signs of a dramatic decline in the health of the population and a deterioration of services at hospitals under financial pressure.

Many Greeks have lost access to healthcare coverage through work and social security plans, and rising poverty levels mean growing numbers who would previously have used the private sector are now flocking to state hospitals. Alongside savage spending cuts, the rise has put an immense strain on a chaotic and corrupt system that was already in decline.

Hospital budgets dropped by 40% between 2007 and 2009, say the Lancet authors. There are reports of understaffing, shortages of medical supplies and patients paying bribes to medical staff to jump queues.

"There are signs that health outcomes have worsened, especially in vulnerable groups," write the experts. There was a 14% rise in the number of Greeks reporting their health as "bad" or "very bad" between 2007 and 2009.

Suicides rose by 17% during the same period, and unofficial 2010 data quoted in parliament mention a 25% rise compared with 2009. The health minister reported a 40% rise in the first half of 2011 compared with the same period in 2010.

"The national suicide helpline reported that 25% of callers faced financial difficulties in 2010 and reports in the media indicate that the inability to repay high levels of personal debt might be a key factor in the increase in suicides," the Lancet authors write. "Violence has also risen, and homicide and theft rates nearly doubled between 2007 and 2009."

Their analysis is based on data from the EU Statistics on Income and Living Conditions. The pressure that the health services are under may account for a rise of 15% between 2007 and 2009 in the numbers who say they did not go to the doctor even though they thought they should. Long waiting times and travel distances to clinics were among the reasons cited.

GP and hospital out-patient care is virtually free, but many Greeks cannot even afford the €5 (£4.30) fee they are required to pay when visiting public out-patient clinics, and doctors say they are often forced to haggle over fees.

Meanwhile, there has been a marked rise in the number of people admitted to hospital – up 24% between 2009 and 2010 and up another 8% in the first half of 2011 compared with the same period last year.

The impact of cuts on drugs services appears particularly troubling. HIV infections rose significantly in 2010, with injecting drug users accounting for half of the rise. The numbers are on course to rise by 52% this year. Many new infections are also linked to rises in prostitution and unsafe sex. Heroin use reportedly rose by 20% in 2009, according to estimates from the Greek Documentation and Monitoring Centre for Drugs. Budget cuts in 2009 and 2010 have meant the loss of a third of the country's outreach programmes.

Health workers in Athens say the economic crisis has contributed to a surge in intravenous drug use in the city. "Since January 2011 we have seen a more than 1000% rise of HIV among intravenous drug users," says Eleni Kokalou who works in the infectious diseases department of Evangelismos Hospital. "Lack of preventive services at community and primary level and funding cuts for the few existing ones, like the syringes exchange program for IDUs, has contributed greatly to the rise," she said.

"Overall, the picture of health in Greece is concerning," write the Lancet authors. "In an effort to finance debts, ordinary people are paying the ultimate price: losing access to care and preventive services, facing higher risks of HIV and sexually transmitted diseases, and in the worst cases losing their lives. Greater attention to health and healthcare access is needed to ensure that the Greek crisis does not undermine the ultimate source of the country's wealth - its people."